U.S. Navy Ship Postmarks

About 1930 USN medical doctor Francis Locy (LO-see) invented the postmark classification system that bears his name. He transferred his copyright to the USCS Universal Ship Cancellation Society, which owns and maintains the Locy System today. This article reviews only the major postmark types and varieties. See website USCS.org for pictures (worth 1,000 words each) and complete information.

Postmark. Legal guarantee of the current date and Post Office location, used to cancel postage stamps and certify documents.

Dial.  Circle with ship name and postmark date inside.
Killer bars. Thick or thin lines at the right of the dial.

Type 1. Rubber, dial with "U.S.S. SHIPNAME" at the top, four thick killer bars.
Rubber cancels bend and break, steel cancels do not.

Type 2. Similar to T-1 with "U.S.S." at the top and "SHIPNAME" at the bottom, shorter killer bars.

Type 3. Rubber, dial "U.S.S." at the top and "SHIPNAME" at the bottom, three killer bars, often with wording in between.

(Type 4 not used.)

Type 5. Similar to T-3 with "U.S.S. SHIPNAME" at the top and three dashes at the bottom, smaller dial and killer bars closer together.
    Type 5k. No dashes.

Type 6. Steel, dial "U.S.S. SHIPNAME" at the top, year date outside dial, oval killer grid of 10 or 12 closely spaced bars.
    Type 6e. Year date inside dial.

Type 7. Steel machine postmark, dial "U.S.S." at the top and "SHIPNAME" at the bottom, seven thin wavy lines.
    Type 7d. Straight lines.
    Type 7q. Six wavy lines.

Type 8. Steel machine flag postmark, used by only eight USN ships.

Type 9. Rubber, dial with smaller circle inside, "U.S.S. SHIPNAME" between the circles, no killer bars.
    Type 9v. "Registered" between the circles.
    Type 9w. "M.O.B." (Money Order Business) between the circles.
    Type 9x. "Parcel Post" between the circles.

Type 10. Steel roller, dial similar to type T-9 with continuous thin wavy lines.

Type F. "Fancy" postmarks not included in types T-1 to T-10, identified by illustration number in the USCS "Catalog of U.S. Naval Postmarks."

Lower case and capital letters define differences of style, wording and placement.

Lower case letters follow the type number.
    a. All killer bars missing or removed.
    b. One or two killer bars missing.
    e. "BR" (branch) in dial.
    f. "New York N.Y." in dial. (All shipboard Post Offices were administrative Branches of the New York NY Post Office.)
    h. Heavier lines.
    j. Lighter lines.
    r. Wide spacing "S H I P N A M E".
    s. Serif letters.
    t. Ship name at top of dial.
    u. Ship name at bottom of dial.
    z. "U.S. NAVY" instead of ship name, for wartime security.

Capital letters set off with (parentheses.)
    (A) Wide spacing "U.  S.  S."
    (B) Narrow spacing "U.S.S."
    (C) Period "." following ship name.
    (C+) Comma "," following ship name.

The killer bars on type T-3 cancels had seams from the molding process. These seams show as separate lines above or below the bars.
    B. Line at bottom
    O. No line.
    T. Line at top.
    X. Bar missing.
Always three letters, one for each bar. For example (OTB) means the top killer bar has O no line, the middle bar has T a line on the Top, and the bottom bar has B a line at the Bottom.

As one example, the USS SHAW postmark at the top of the page is classified
    T-3r(AC-BBT)

This article has reviewed only the main types of USN shipboard cancels. The Locy System includes other postmarks and suffixes not listed. See the USCS website for complete information.

The Universal Ship Cancellation Society, founded in 1932, is Affiliate #98 of the American Philatelic Society and shares the same standards and ethics.